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371.
Nicole Wagner Kay-Dietrich Wagner Gunnar Schley Sarah E Coupland Heinrich Heimann Rosemarie Grantyn Holger Scholz 《Cell growth & differentiation》2002,13(7):297-305
We have demonstrated recently that Wilms' tumor suppressor 1 (Wt1),in addition to its role in genitourinary formation,is required for the differentiation of ganglion cells in the developing retina. Here we provide further evidence that Wt1 is associated with neuronal differentiation. Thus, the retinoblastoma-derived human cell line, Y-79, contained robust amounts of Wt1 mRNA and protein. Wt1 expression was down-regulated upon laminin-induced differentiation of Y-79 into neuron-like cells. Inhibition of Wt1 with antisense oligonucleotides dramatically reduced the capacity of undifferentiated Y-79 cells to undergo neuronal differentiation, whereas sense and missense oligonucleotides had no effect. Wt1 immunoreactivity was also detected in solid retinoblastomas, in which it resided mainly in areas with moderate proliferative activity. These findings suggest a role for Wt1 in the differentiation of retinoblastoma cells. Furthermore, Wt1 expression in retinoblastoma may reflect the potential of these tumors to initiate the early steps of neuronal differentiation. 相似文献
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It is clear that the well-described phenomenon of epithelial–mesenchymal transition (EMT) plays a pivotal role in embryonic
development, wound healing, tissue regeneration, organ fibrosis and cancer progression. EMTs have been classified into three
subtypes based on the functional consequences and biomarker context in which they are encountered. This review will highlight
findings on type II EMT as a direct contributor to the kidney myofibroblast population in the development of renal fibrosis,
specifically in diabetic nephropathy, the signalling molecules and the pathways involved in type II EMT and changes in the
expression of specific miRNA with the EMT process. These findings have provided new insights into the activation and development
of EMT during disease processes and may lead to possible therapeutic interventions to suppress EMTs and potentially reverse
organ fibrosis. 相似文献
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Yemisrach Zewdie Seralegne Cynthia Khamala Wangamati Rosemarie D. L. C. Bernabe Bobbie Farsides Abraham Aseffa Martha Zewdie 《Developing world bioethics》2023,23(1):50-58
Few studies in sub-Saharan Africa evaluate Institutional Review Boards (IRBs) capacity. The study aims to explore the composition of IRBs, training, and challenges experienced in the ethics review processes by members of research institutions and universities in Addis Ababa, Ethiopia. Our findings indicate that most IRBs members were trained on research ethics and good clinical practice. However, majority perceived the trainings as basic. IRB members faced several challenges including: investigators wanting rapid review; time pressure; investigators not following checklists; limited expertise in reviewing clinical trials, studies on genetics, and traditional medicine; lack of IRB offices for administrative work; competing tasks; limited staffing and the lack of a standardized review system. There is need for advanced training on research ethics to meet the evolving research needs. In addition, investments in IRBs are needed in terms of funding, and physical and human resources in Addis Ababa and Ethiopia in general. 相似文献
377.
Assessing German farmers’ attitudes regarding nature conservation set-aside in regions dominated by arable farming 总被引:2,自引:0,他引:2
Rosemarie Siebert Gert Berger Jana Lorenz Holger Pfeffer 《Journal for Nature Conservation》2010,18(4):327-337
This paper presents an analysis of the attitudes of farmers towards a policy approach that combines the instrument of set-aside of farmland with agri-environmental measures under the Common Agricultural Policy (CAP) for achieving nature goals. One of the stated objectives of current agricultural and environmental policies is to give greater consideration to issues of nature conservation in agricultural landscapes. To fulfil this objective, there is an urgent need to develop approaches that, on the one hand, are capable of delivering tangible improvements in the ecological situation and nature conservation in agriculture and, on the other hand, are structured in such a way that farmers are willing to put them into practice. In addition, such approaches need to be economical and affordable for society. The Leibniz-Centre for Agricultural Landscape Research (ZALF) has developed the concept of ‘nature-conservation set-aside’, especially for landscapes that are under predominantly arable use. Conservation set-aside refers to parts of arable farmland especially well suited to nature conservation, which are mandatorily withdrawn from agricultural production (for those who claim payment) and on which ecologically valuable habitats are created through specific management activities. To determine what kind of problems might arise for farmers in the course of implementing this concept as an agri-environmental measure, a survey was carried out in four largely arable regions of Germany. The results of this survey show the attitudes of German farmers regarding set-aside farmland for nature conservation in regions dominated by arable farming, and they demonstrate which factors influence the implementation of conservation set-aside. 相似文献
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Asem Habes Abu Alloush Piero Attilio Bianco Sadeer Amashah Enrico Busato Amre Mahasneh Mahmoud AlShoubaki Alberto Alma Rosemarie Tedeschi Fabio Quaglino 《The Annals of applied biology》2023,182(2):159-170
During field surveys conducted in northern Jordan from June to November 2020, phytoplasma-like symptoms, including leaf yellowing/reddening and rolling, little leaf and witches' broom were observed in pomegranate. Disease incidence in 22 surveyed orchards ranged from 30% to 65%. Nested PCR-based amplification of 16S rRNA gene detected phytoplasmas in 17% of collected symptomatic pomegranate trees. Amplicon nucleotide sequence analyses allowed attributing the detected phytoplasmas to ‘Candidatus Phytoplasma solani’, ‘Ca. P. aurantifolia’, ‘Ca. P. asteris’ and ‘Ca. P. ulmi’. These phytoplasmas were found in plants showing specific symptoms and differentially distributed in the considered locations. Additionally, three cicadellids (Macrosteles sexnotatus, Cicadulina bipunctata and Psammotettix striatus) and two non-crop plants (Plantago major and Capsicum annuum) resulted hosting ‘Ca. P. asteris’ strains, and one cicadellid (Balclutha incisa) was carrying a ‘Ca. P. solani’ strain. A new pomegranate disease complex associated with multiple phytoplasmas, including ‘Ca. P. aurantifolia’ and ‘Ca. P. ulmi’, never reported before in this host plant, is described here. Moreover, preliminary indications are provided on its possible epidemiology in Jordan, involving two putative insect vectors (M. sexnotatus, B. incisa) first reported in the Country. 相似文献